Design of a Hybrid Light Guiding Plate With High Luminance for Backlight System Application

Abstract

We proposed a novel backlight system, which consisted of a hybrid light guide plate (LGP) and one diffuser sheet. The hybrid LGP contains a flat plate without any microstructures and one layer of optically patterned film (OPF). Comparing with the conventional edge-lit backlight system, the on-axis luminance could be improved to 6.1 x by using the novel backlight system and the half-luminance angle decreased from 21 deg to 10 deg in vertical direction, and decreased from 21 deg to 6 deg in horizontal direction. At the same time, this design also achieved a uniformity of illumination of 89%. The design can predigest the fabrication and reduce the number of components. Moreover, since the microstructures arrangement was periodical, user could use light-emitting diodes (LEDs) on the both sides. When user turned on both side LEDs, the on-axis luminance were improved 1.7 x comparing with turning on single side LEDs.